Skeletal Radiology最新文献

Krabbe disease is an autosomal recessive leukodystrophy where a deficiency of the galactosylceramide beta-hydrolase enzyme leads to accumulation of toxic substances which cause demyelination in both central and peripheral nervous systems. It is classified into early infantile, late infantile, juvenile and adult types based on the age of presentation. MRI of the brain in patients with Krabbe disease shows bilaterally symmetrical T2 hyperintense signal in the periventricular and deep white matter and in the corticospinal tracts. Patients can have peripheral neuropathy, which, on imaging, is commonly seen in the form of thickening and enhancement of cranial nerves and nerve roots of cauda equina. Our patient, a child aged eleven years, had intracranial lesions along with brachial plexopathy. This is the first described case of juvenile-onset Krabbe disease with brachial plexus involvement.

Objectives: To evaluate the impact of calcium suppression (CaSupp) imaging of spectral computed tomography (SpCT) on fracture detection in clinical routine in the acute trauma setting of the hand and wrist.

Materials and methods: Retrospective inclusion of 125 patients who underwent both X-ray and SpCT examinations of the hand and wrist in an acute trauma setting. Two independent readers evaluated fracture presence on X-ray, conventional CT, and conventional CT plus CaSupp images (time interval 4 weeks, each). Bone bruise (BBr) presence was evaluated on CaSupp images. Sensitivity and specificity were calculated according to the consensus reading as the reference standard.

Results: Of the 125 patients (mean age, 55 years ± 19.5 [SD]; 67 female), 120 presented with at least one fracture, for a total of 212 fractured bones. Sensitivity was increased significantly for both readers in CT + CaSupp (94.3 and 97.2%) compared to conventional CT (88.2 and 90.1%, p < .01) and X-ray (72.6 and 75.9%, p < .01). Specificity was 99.9 and 100% for CT + CaSupp, 99.8 and 99.9% for conventional CT, and 99.4 and 99.9% for X-ray. Reader 1 detected 13 additional fractures in CT + CaSupp compared to conventional CT alone, while Reader 2 detected 15 additional fractures. BBr was seen in 58% of all fractures, in 76% of multifragmentary fractures, and in 13% of avulsion fractures. Inter-reader κ was almost perfect for X-ray (κ = .85), CT and CT + CaSupp (κ = .95), and substantial for BBr (κ = .61).

Conclusion: CaSupp images in combination with conventional CT images significantly improved sensitivity for acute trauma fracture detection in the hand and wrist compared to conventional CT images alone and X-ray.

Objective: To synthesize magnetic resonance imaging (MRI) features and their reported diagnostic performance that differentiate benign from malignant soft-tissue tumors in alignment with the 2020 World Health Organization classification.

Materials and methods: A systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Embase, Scopus, and the Cochrane Central Register of Controlled Trials were searched through July 2024. Eligible studies reported MRI feature frequencies or diagnostic accuracy for common soft-tissue tumor subtypes. Reviews, case reports, duplicates, non-English publications, and studies outside the scope were excluded. Quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2).

Results: Seventy-six studies met inclusion criteria. In lipomatous tumors, homogeneous fat signal and thin septa supported lipoma, whereas thick or nodular septa and enhancement favored atypical or well-differentiated liposarcoma. Myxofibrosarcoma often demonstrated an infiltrative fascial "tail." Vascular lesions included angioleiomyoma with a reticular T2 pattern and glomus tumor with marked T2 hyperintensity and avid enhancement. In peripheral nerve sheath tumors, lower apparent diffusion coefficient values and peritumoral edema favored malignancy. Heterogeneity in imaging protocols precluded meta-analysis; results were summarized descriptively by subtype.

Conclusion: Consolidated MRI patterns-such as septal morphology in lipomatous tumors, the fascial tail in myxofibrosarcoma, characteristic T2 patterns in vascular lesions, and diffusion and edema cues in nerve sheath tumors-support differentiation of benign and malignant entities, enhance reader confidence, and inform biopsy and management. Standardized prospective studies are needed to validate these thresholds and improve generalizability.

Objectives: To characterize ankle magnetic resonance imaging (MRI) features in pediatric and young adult patients with familial Mediterranean fever (FMF) and compare them with those in juvenile idiopathic arthritis (JIA) and chronic nonbacterial osteomyelitis (CNO) in order to identify distinguishing or overlapping imaging features among the three conditions.

Methods: Twelve ankle MRI examinations from 11 patients with FMF (mean age 12.4 years, 7 females) were retrospectively evaluated and compared with 22 examinations from 17 patients diagnosed with JIA (12 patients/14 ankles, mean age 14.3 years, 8 females) or CNO (5 patients/8 ankles, mean age 10.2 years, 3 females). Calcaneal enthesitis features were assessed at the insertion site of the Achilles tendon, plantar fascia, and the long plantar tendon. Also evaluated were the presence of diffuse calcaneal bone marrow edema (BME), midfoot arthritis, synovitis, and tenosynovitis.

Results: Insertional calcaneal BME, an enthesitis-related feature, was more prevalent in FMF patients compared to both JIA and CNO, while among the three evaluated entheses, long plantar tendon enthesitis was significantly more prevalent in FMF patients only compared to those with JIA (p < 0.001). CNO presented a predominantly osseous inflammation pattern with diffuse calcaneal BME (87.5%, p < 0.001) and additional hindfoot BME (75%, p < 0.002), clearly distinct from FMF. Synovitis and tenosynovitis were more commonly observed in JIA patients, although the differences compared to FMF and CNO were not statistically significant.

Conclusion: Although imaging features overlap among FMF, CNO, and JIA, distinct MRI patterns emerge: enthesitis predominates in FMF, osteitis in CNO, and synovitis in JIA.

Objectives: The transverse trochlear ridge (TTR) is an anatomic variant of the ulnar trochlear groove. This study evaluated the prevalence and imaging characteristics of the TTR on MRI and radiographs in children, adolescents, and young adults.

Materials and methods: This retrospective analysis included 178 MRI examinations and 95 corresponding radiographs of patients aged 4-25 years. The presence or absence of the TTR was evaluated. The width, height, and depth of the TTR were measured. The sensitivity and specificity of radiography to detect TTRs were evaluated compared with MRI as the reference standard. Binomial logistic regression analysis was used to compare the effects of age and gender on the prevalence of TTR.

Results: TTR was observed on 149 of 178 (83.7%) elbow MRIs. Mean width, height, and depth were 20.6 ± 3.0 mm, 4.2 ± 1.2 mm, and 2.0 ± 0.7 mm, respectively. Comparing increasing age in years with the prevalence of the TTR revealed a statistically significant odds ratio of 1.119 (95% CI; p = 0.012). The maximum predicted probability was a prevalence of 96% for TTR at the age of 25. Sensitivity and specificity values of the TTR on radiographs were 29.6% and 92.9%. Cohen's kappa for the inter-rater agreement for the prevalence of the TTR on MRI was 0.740.

Conclusions: The predicted prevalence of TTR demonstrated an age-dependent increase in the prevalence up to 17 years of age. The size of the TTR also demonstrated an age‑dependent increase during adolescence. The high frequency of TTR on MRI indicates that TTR represents a common variant.

The posterolateral corner (PLC) of the knee comprises a complex arrangement of anatomical and biomechanical structures. Owing to their variability, small size, and the inconsistent terminology found in the literature, these structures have historically been referred to as the "dark side of the knee". This review aims to summarize the relevant anatomy and MR anatomy of the PLC stabilizers, illustrate key MRI findings in acute and chronic injuries, and provide practical considerations for structured diagnosis and reporting. The main stabilizers of this region include the lateral collateral ligament (LCL), the popliteofibular ligament (PFL), and the popliteus myotendinous complex. Together, these elements provide resistance against varus forces and external tibial rotation, with additional compensatory roles in the presence of cruciate ligament insufficiency. Injury mechanisms are diverse, commonly involving direct high-energy trauma, hyperextension, or rotational-varus-hyperextension stress in sports-related activities. Although PLC lesions represent nearly one-third of all ligamentous injuries of the knee, isolated involvement is uncommon, with frequent associations with posterior and anterior cruciate ligament tears. Accurate imaging evaluation, particularly with magnetic resonance imaging (MRI), is fundamental for timely diagnosis, guiding appropriate management, and reducing the risk of chronic posterolateral instability, cruciate graft failure, and progression to osteoarthritis.

Phosphaturic mesenchymal tumours (PMTs) are rare neoplasms that secrete fibroblast growth factor-23 (FGF-23), causing tumour-induced osteomalacia (TIO). Histological overlap with juvenile psammomatoid ossifying fibroma (JPOF) can lead to diagnostic difficulty, particularly outside the craniofacial skeleton. A 4-year-old girl presented with a painful forearm swelling. Radiographs demonstrated a fibro-osseous lesion in the radius and biopsy was initially non-diagnostic, leading to a presumptive diagnosis of fibrous dysplasia. Over the next 6 years, the lesion enlarged, and at age 10, the patient developed genu valgum with biochemical evidence of hypophosphataemic rickets (low phosphate, raised alkaline phosphatase, elevated FGF-23). Medical therapy corrected the rickets, though deformity required guided growth surgery. At age 13, a repeat biopsy of the enlarging lesion revealed a fibro-osseous tumour with spindle stroma and psammomatoid ossicles, negative for GNAS mutation, and consistent with a phosphaturic mesenchymal tumour, connective tissue variant. This case highlights a rare radiologic presentation of PMT involving a long bone, with imaging features closely mimicking fibrous dysplasia and histological overlap with JPOF. The rapid progression of imaging findings, discordant metabolic abnormalities and markedly elevated FGF-23 levels poses a diagnostic challenge. As such, fibrous dysplasia-like lesions of the extremities in the setting of hypophosphataemic rickets should prompt consideration of PMT.

Septic arthritis of the knee is an acute infection that can rapidly destroy articular cartilage if not promptly recognized and treated. Early diagnosis is often difficult because symptoms overlap with crystal or inflammatory arthropathies and post-traumatic effusions, while fever and laboratory markers may be absent or nonspecific. Synovial fluid analysis remains the diagnostic cornerstone, but imaging is essential to confirm effusion, define the extent of synovitis and periarticular involvement, and detect complications such as osteomyelitis or abscess. Radiography provides a rapid baseline, ultrasound is highly sensitive for effusion and guides aspiration, and CT is valuable for cortical destruction and deep soft-tissue mapping. MRI offers the most comprehensive early assessment, revealing synovial enhancement, bone-marrow edema, and occult abscesses. Nuclear medicine studies, including labeled leukocyte scintigraphy and FDG PET/CT, are useful in complex or periprosthetic settings and for monitoring therapy. Staphylococcus aureus remains the leading pathogen, followed by streptococci and Gram-negative bacilli, with atypical and fungal infections mainly in immunocompromised hosts. A stepwise, multimodality imaging strategy enhances diagnostic confidence and guides timely intervention, while advances such as metal-artifact reduction, radiomics, and hybrid imaging hold promise for improving accuracy and standardization in native knee infections.